NEW ORLEANS (AP)  An explosion occurred on an offshore oil and gas platform in the Gulf of Mexico on Thursday, killing one person and injuring three.

The Bureau of Safety and Environmental Enforcement said Fieldwood Energy reported the explosion on its Echo Platform just before 3 p.m. about 12 miles off Louisiana”s coast.

In a statement late Thursday, the Houston, Texas-based company said it was “an isolated incident that has been fully contained.” The company said the person who was killed was an employee of a contractor, and another contractor employee was seriously injured. All other personnel working at the facility were accounted for, Fieldwood Energy said in the email statement.

The bureau said in a statement that the platform was not in production at the time of the explosion and damage was limited to the area. The statement said there was no indication that any oil had spilled into the ocean.

Bureau spokeswoman Chauntra Rideaux said the injured workers were being treated at a medical facility. She did not say where or have their conditions.

She said the explosion is under investigation.

The explosion occurred about two months after a contractor was killed and two others hurt during maintenance work in September on a Chevron natural gas pipeline, also off the Louisiana coast. The cause remains under investigation.